JP2016024057A - Method for correcting stress value in infrared stress measurement system, and infrared stress measurement system using the same - Google Patents
Method for correcting stress value in infrared stress measurement system, and infrared stress measurement system using the same Download PDFInfo
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本発明は、引張あるいは圧縮応力を測定対象物に繰返し加え、この測定対象物を赤外線カメラによって撮像して前記測定対象物の温度振幅を測定し、この測定結果から前記測定対象物の応力値を求める赤外線応力測定システムに関するものである。 In the present invention, tensile or compressive stress is repeatedly applied to an object to be measured, the object to be measured is imaged by an infrared camera, and the temperature amplitude of the object to be measured is measured. From the measurement result, the stress value of the object to be measured is calculated. The present invention relates to a desired infrared stress measurement system.
従来、赤外線応力測定の補正方法としては、例えば、非特許文献１〜非特許文献３に記載されているようなものが報告されている。 Conventionally, as a correction method of infrared stress measurement, for example, those described in Non-Patent Document 1 to Non-Patent Document 3 have been reported.
非特許文献１には、コーティング膜が塗布された測定対象物の応力補正方法が記載されている。前記コーティング膜の膜厚が前記測定対象物の基材に比べて薄いため、基材の温度とコーティング膜の温度はそれぞれ一様と仮定し、その条件の下で熱伝導方程式を解くことで加振周波数によって減衰する応力値の補正を行っている。ただし、熱弾性効果による発熱は基材のみで発生し、コーティング膜の熱弾性効果による発熱は無いと仮定している。加振周波数増加により、測定対象物の測定応力が減衰する要因は、基材からコーティング膜への移動熱量が周波数の増加に伴い減少することに起因すると述べられている。しかしながら、補正のための理論解の導出過程で、膜厚が０と極限をとる場合と、膜厚が有限値とする場合があり、膜厚の近似的扱いに制限があるため条件によって成り立たない。 Non-Patent Document 1 describes a stress correction method for a measurement object to which a coating film is applied. Since the thickness of the coating film is thinner than the substrate of the object to be measured, it is assumed that the temperature of the substrate and the temperature of the coating film are uniform, and are added by solving the heat conduction equation under the conditions. The stress value that attenuates according to the vibration frequency is corrected. However, it is assumed that heat generation due to the thermoelastic effect occurs only in the base material and there is no heat generation due to the thermoelastic effect of the coating film. It is stated that the factor that the measurement stress of the measurement object attenuates due to the increase of the excitation frequency is that the amount of heat transferred from the substrate to the coating film decreases as the frequency increases. However, in the process of deriving the theoretical solution for correction, there are cases where the film thickness takes a limit of 0 and the film thickness may be a finite value. .
非特許文献２では、非特許文献１と同様に、コーティング膜の熱弾性効果による発熱は無いと仮定されている。更に、熱の伝導をサーマルウエブと捉え、コーティング膜内で前記測定対象物の基材とコーティング膜の界面、コーティング膜と空気との界面で繰り返される反射によって減衰する熱を足し合わせることで、加振周波数の増加による応力値が減衰する状態を表わすことができると述べている。しかしながら、低熱伝導基材の場合、熱伝導の影響を無視できず基材で生じた熱がコーティング膜へ伝わるが、それによって基材の熱が減ることはないためこの近似はコーティング膜への移動熱量が多い場合、基材とコーティング膜の物性値が近い場合、Rs(反射係数）＝−１付近以外は、コーティング膜表面の温度が減衰せず成り立たない。 In Non-Patent Document 2, as in Non-Patent Document 1, it is assumed that there is no heat generation due to the thermoelastic effect of the coating film. Furthermore, heat conduction is regarded as a thermal web, and the heat attenuated by repeated reflections at the interface between the substrate of the measurement object and the coating film and at the interface between the coating film and air in the coating film is added. It states that the stress value due to the increase of the vibration frequency can be attenuated. However, in the case of a low thermal conductivity substrate, the effect of heat conduction cannot be ignored and the heat generated in the substrate is transferred to the coating film, but this approximation does not reduce the heat of the substrate, so this approximation is transferred to the coating film. When the amount of heat is large, when the physical property values of the substrate and the coating film are close to each other, the temperature of the coating film surface is not attenuated except in the vicinity of Rs (reflection coefficient) = − 1.
非特許文献３は、非特許文献２の改良したもので、非特許文献２の理論解にRs（反射係数）＝−１を代入することによって補正できることを述べている。しかしながら、低熱伝導基材の場合、基材とコーティング膜の物性値が近い場合は成り立たない。 Non-Patent Document 3 is an improvement of Non-Patent Document 2 and states that it can be corrected by substituting Rs (reflection coefficient) = − 1 into the theoretical solution of Non-Patent Document 2. However, in the case of a low thermal conductive base material, it is not possible if the physical property values of the base material and the coating film are close.
赤外線サーモグラフィを用いた熱弾性効果に基づいて測定される赤外線応力測定法の応力値の補正方法については、多くの報告がなされている。しかしながら、前提条件としてコーティング膜の熱弾性効果による発熱現象や基材の厚み、熱伝導状態などが考慮されていないため、低熱伝導基材や基材とコーティング膜の物性値が近い条件下では、実績で生じる加振周波数にともなうコーティング膜表面の温度減衰を理論計算で忠実に表現することが不可能であった。その結果、測定して得られた応力値の減衰を完全に補正することができなかった。 There have been many reports on methods for correcting stress values in infrared stress measurement methods that are measured based on thermoelastic effects using infrared thermography. However, since the heat generation phenomenon due to the thermoelastic effect of the coating film, the thickness of the base material, the heat conduction state, etc. are not considered as preconditions, under the conditions where the physical property values of the low heat conductive base material and the base material and the coating film are close, It was impossible to faithfully express the temperature decay of the coating film surface with the vibration frequency generated in the actual results by theoretical calculation. As a result, the attenuation of the stress value obtained by the measurement could not be completely corrected.
本発明は、上記課題を解決することが可能な赤外線応力測定で得られる応力値の補正方法およびその方法を用いた赤外線応力測定システムを提供することを目的とする。 An object of this invention is to provide the correction method of the stress value obtained by the infrared stress measurement which can solve the said subject, and the infrared stress measurement system using the method.
前記従来の課題を解決するため、本発明の赤外線応力測定システムにおける応力値の補正方法は、基材とコーティング膜から構成される測定対象物を加振し、前記測定対象物を赤外線カメラで撮影して前記測定対象物の温度振幅を測定し、この測定結果から前記測定対象物の応力値を求める赤外線応力測定システムにおいて、基材とコーティング膜両方の熱伝導および熱弾性効果に基づく１次元の熱伝導方程式から求められるコーティング膜表面の温度振幅の理論解を、異なる振動周波数によって得られる熱弾性効果に基づく温度変化成分および位相成分の周波数特性に対して最小二乗法によりカーブフィッティングさせることによって前記コーティング膜表面の理論解の変数を同定し、コーティングによる熱伝導の影響を補正する、ことを特徴とする。 In order to solve the above-mentioned conventional problems, the stress value correcting method in the infrared stress measurement system of the present invention is to vibrate a measurement object composed of a base material and a coating film, and photograph the measurement object with an infrared camera. In the infrared stress measurement system for measuring the temperature amplitude of the measurement object and obtaining the stress value of the measurement object from the measurement result, the one-dimensional based on the heat conduction and thermoelastic effects of both the substrate and the coating film By applying the theoretical solution of the temperature amplitude of the coating film surface obtained from the heat conduction equation to the frequency characteristic of the temperature change component and the phase component based on the thermoelastic effect obtained by different vibration frequencies by curve fitting by the least square method. Identify the variables of the theoretical solution on the coating film surface, and correct the influence of heat conduction by the coating. And butterflies.
また、本発明の赤外線応力測定システムは、測定対象物を加振し、前記測定対象物を赤外線カメラで撮影し、熱弾性効果を用いて前記測定対象物に作用する応力値を計算する赤外線応力測定システムであって、測定対象物を撮影する赤外線カメラと、前記赤外線カメラの温度振幅画像を処理して前記測定対象物の応力値を求める情報処理装置とを有し、前記情報処理装置は、基材とコーティング膜両方の熱伝導および熱弾性効果に基づく１次元の熱伝導方程式から求められるコーティング膜表面の温度振幅の理論解を、異なる振動周波数によって得られる熱弾性効果に基づく温度変化成分および位相成分の周波数特性に対して最小二乗法によりカーブフィッティングさせることによって前記コーティング膜の表面の理論解の変数を同定し、前記コーティング膜による熱伝導の影響を補正して前記測定対象物に作用する応力値を計算する、ことを特徴とする。 Further, the infrared stress measurement system of the present invention excites a measurement object, images the measurement object with an infrared camera, and calculates a stress value acting on the measurement object using a thermoelastic effect. A measurement system, comprising: an infrared camera that images a measurement object; and an information processing device that processes a temperature amplitude image of the infrared camera to obtain a stress value of the measurement object; A theoretical solution of the temperature amplitude of the coating film surface obtained from a one-dimensional heat conduction equation based on the heat conduction and thermoelastic effects of both the base material and the coating film, and a temperature change component based on the thermoelastic effect obtained by different vibration frequencies and The variable of the theoretical solution on the surface of the coating film is identified by curve fitting to the frequency characteristic of the phase component by the least square method, The effect of thermal conduction by coating by correcting calculating a stress value which acts on the object to be measured, characterized in that.
本発明によると、基材とコーティング膜両方の熱伝導および熱弾性効果に基づく１次元の熱伝導方程式から求められるコーティング膜表面の温度振幅の理論解を、異なる振動周波数によって得られる熱弾性効果に基づく温度変化成分および位相成分の周波数特性に対して最小二乗法によりカーブフィッティングさせることによって前記コーティング膜表面の理論解の変数を同定し、コーティングによる熱伝導の影響を補正するので、正しい応力値を求めることができる。特に、基材の熱伝導率が低い材料もしくは、基材とコーティング膜の物性値が近い材料の測定対象物の応力値を求めるのに効果が大きい。 According to the present invention, the theoretical solution of the temperature amplitude of the coating film surface obtained from the one-dimensional heat conduction equation based on the heat conduction and thermoelastic effect of both the substrate and the coating film is converted into the thermoelastic effect obtained by different vibration frequencies. The variable of the theoretical solution of the coating film surface is identified by curve fitting to the frequency characteristics of the temperature change component and phase component based on the least square method, and the effect of heat conduction by the coating is corrected. Can be sought. In particular, it is highly effective in obtaining the stress value of a measurement object of a material having a low thermal conductivity of the substrate or a material having physical properties close to those of the substrate.
また、１次元の熱伝導方程式の温度振幅の理論解を構成する変数は、基材とコーティング膜の物性値および厚さの比で表すことができるため、基材もしくはコーティング膜のどちらかの変数を構成する物性値さえわかれば、もう一方の物性値を求めることもできる。 In addition, since the variable that constitutes the theoretical solution of the temperature amplitude of the one-dimensional heat conduction equation can be expressed by the ratio of the physical property value and the thickness of the base material and the coating film, the variable of either the base material or the coating film The other physical property value can be obtained as long as the physical property value that constitutes is known.
更に、加振周波数を変化させて得られる熱弾性効果に基づく温度振幅成分および位相成分の周波数特性を構成するデータ点数は減衰曲線の形状を表現できる測定点数を用いることで正確な補正を可能にする。 In addition, the number of data composing the frequency characteristics of the temperature amplitude component and phase component based on the thermoelastic effect obtained by changing the excitation frequency can be accurately corrected by using the number of measurement points that can represent the shape of the attenuation curve. To do.
更に、放射率を均一に向上させるために必要なコーティング膜による熱伝導の影響を補正する機能を備えることによって、コーティング膜による減衰を補正でき、基材の熱伝導特性に関係なく正確な赤外線応力測定を可能にする。 Furthermore, by providing the function to correct the influence of heat conduction by the coating film necessary to improve the emissivity uniformly, the attenuation by the coating film can be corrected, and the accurate infrared stress is applied regardless of the heat conduction characteristics of the substrate. Enable measurement.
なお、本発明のコーティング膜による減衰を補正方法は、補正のために理論解を解く過程で未知の変数を物性値および厚さの比で表すことから、基材の物性値、厚みがわかれば、コーティング膜の物性値、厚みを計算から求めることも可能である。 In the method for correcting attenuation by the coating film of the present invention, an unknown variable is expressed by a ratio of a physical property value and a thickness in the process of solving a theoretical solution for correction. The physical property value and thickness of the coating film can also be obtained by calculation.
本発明の赤外線応力測定システムは、基材とコーティング膜両方の熱伝導および熱弾性効果を考慮した１次元の熱伝導方程式から求められるコーティング膜表面の温度振幅の理論解を、異なる振動周波数によって得られる熱弾性効果に基づく温度変化成分および位相成分の周波数特性に対して最小二乗法によりカーブフィッティングさせることによって前記コーティング膜表面の理論解の変数を同定し、コーティング膜による熱伝導の影響を補正することを特徴とする。 The infrared stress measurement system of the present invention obtains a theoretical solution of the temperature amplitude of the coating film surface obtained from a one-dimensional heat conduction equation considering the heat conduction and thermoelastic effects of both the substrate and the coating film at different vibration frequencies. The variable of the theoretical solution of the coating film surface is identified by curve fitting to the frequency characteristics of the temperature change component and the phase component based on the thermoelastic effect, and the effect of heat conduction by the coating film is corrected. It is characterized by that.
１次元の熱伝導方程式の温度振幅の理論解を構成する変数は、基材とコーティング膜の物性値および厚さの比で表され、変数を構成する物性値はヤング率、ポアソン比、密度、定圧比熱、熱膨張係数、熱伝導率、厚さである。またその変数の数は１次元の熱伝導方程式を用いていることから、７個以上必要であることを特徴とする。 The variable that constitutes the theoretical solution of the temperature amplitude of the one-dimensional heat conduction equation is expressed by the ratio between the physical property value and the thickness of the substrate and the coating film, and the physical property value that constitutes the variable is Young's modulus, Poisson's ratio, density, Specific pressure specific heat, thermal expansion coefficient, thermal conductivity, thickness. Further, since the number of variables uses a one-dimensional heat conduction equation, seven or more variables are required.
以下に補正に用いられる理論解析について、詳細を説明する。熱弾性応力測定に用いられる熱弾性効果は式（1）で表される。 Details of the theoretical analysis used for correction will be described below. The thermoelastic effect used for thermoelastic stress measurement is expressed by equation (1).
ここで、ａは式（2）で表される熱拡散率，Kは式（3）で表される熱弾性定数である。 Here, a is the thermal diffusivity represented by the formula (2), and K is the thermoelastic constant represented by the formula (3).
また、系が断熱である(ａ＝０)と仮定でき、かつ温度変化が微小である場合、式（1）は次式で表される。
Further, when it can be assumed that the system is adiabatic (a = 0) and the temperature change is minute, Equation (1) is expressed by the following equation.
ここで、厚さをL，熱伝導率をｋ，線膨張係数をα，密度をρ，定圧比熱をC，縦弾性係数をE，Poisson比をｖ，熱拡散率をａ，熱弾性定数をKと定義する。これらの物理量において添字ｃはコーティング膜を表し、添字ｍは基材を表す。熱拡散率ａ，熱弾性定数Kは次式で表される。 Here, the thickness is L, the thermal conductivity is k, the linear expansion coefficient is α, the density is ρ, the constant pressure specific heat is C, the longitudinal elastic modulus is E, the Poisson ratio is v, the thermal diffusivity is a, and the thermoelastic constant is Define as K. In these physical quantities, the suffix c represents a coating film, and the suffix m represents a substrate. The thermal diffusivity a and the thermoelastic constant K are expressed by the following equations.
熱弾性応力測定では、断熱と仮定できる場合、式（5）で表される熱弾性効果に基づいて応力が算出される。しかし非断熱である場合、熱伝導方程式には拡散項が加わるため、基礎式は式（1）となる。今、基材の応力は一様であるため、ｚ軸方向の１次元熱伝導のみを考えると、式（1）から次式が得られる。 In thermoelastic stress measurement, when heat insulation can be assumed, stress is calculated based on the thermoelastic effect expressed by Equation (5). However, in the case of non-adiabatic, the diffusion equation is added to the heat conduction equation, so the basic equation becomes equation (1). Now, since the stress of the substrate is uniform, considering only the one-dimensional heat conduction in the z-axis direction, the following equation is obtained from equation (1).
次に、式（14）を時刻ｔについてフーリエ変換を行う。 Next, the Fourier transform is performed on the time (t) in the equation (14).
ここで、熱放射に基づく温度測定の特徴について考える。赤外線カメラでは測定対象物から放射される赤外線を受光し、その強度から測定対象物の温度を算出している。その算出の際には、十分黒体と考えられる物体における実験的な温度と放射強度の関係が用いられる。しかし、コーティングを施した場合でも実際の測定対象物は黒体と異なるため、実対象物における放射赤外線の強度から算出された温度は実際の温度より低くなる。そのため、測定対象物の真の温度Ｔtrueと赤外線カメラで測定される測定対象物の温度Ｔinfraredの関係は、コーティング膜表面の赤外線放射率εによって次式で表される。 Here, the characteristics of temperature measurement based on thermal radiation will be considered. The infrared camera receives infrared rays emitted from the measurement object, and calculates the temperature of the measurement object from its intensity. In the calculation, the relationship between experimental temperature and radiation intensity in an object considered to be a sufficiently black body is used. However, since the actual measurement object is different from the black body even when the coating is applied, the temperature calculated from the intensity of the radiant infrared rays in the actual object is lower than the actual temperature. Therefore, the relationship between the true temperature T true of the measurement object and the temperature T infrared of the measurement object measured by the infrared camera is expressed by the following equation by the infrared emissivity ε of the coating film surface.
Ｔinfrared＝εＴtrue （40）
ここで放射率εは必ず０≦ε≦１を満たす。また、黒体ではない物体では輻射強度が指向性を有することや、内部から放射された赤外線が物体を透過して赤外線カメラで検出されることも知られている。しかし、検討ではコーティングによって放射率を十分に高めれば、それらについては無視できるものとした。すなわち、測定対象物のコーティング膜から放射される赤外線は指向性を有しておらず、かつその表面から放射される赤外線のみが赤外線カメラで検出されると仮定した。
T infrared = εT true (40)
Here, the emissivity ε always satisfies 0 ≦ ε ≦ 1. It is also known that radiation intensity is directional for an object that is not a black body, and that infrared rays emitted from the inside pass through the object and are detected by an infrared camera. However, in the study, if the emissivity is sufficiently increased by the coating, they can be ignored. That is, it was assumed that the infrared rays emitted from the coating film of the measurement object have no directivity and only the infrared rays emitted from the surface are detected by the infrared camera.
したがって、式（34）にｚ＝Lｍ＋Lｃを代入し、 Therefore, substituting z = L m + L c into equation (34),
次に、一様な正弦波状の曲げモーメントが作用する場合について厚さ方向における１次元熱伝導の理論解析を行い、コーティング膜表面温度の理論解を導出、の補正方法について説明する。基材の片面にコーティングが施されている場合、図３のように基材内の中立面とｚ軸の交点が原点となるよう座標軸を設定する。その場合、測定対象物には図３のｘ軸方向のみの単軸曲げモーメントが加わり、その大きさは正弦波状に変動する。したがって、基材におけるｙ軸方向の垂直応力振幅はｚ軸方向に関して直線的な分布となる。また、基材の変形に応じてコーティング膜も変形すると考えて、基材とコーティング膜の界面でひずみは常に等しく、かつｚ軸方向に一様であると仮定する。よって基材とコーティング膜における応力振幅およびひずみ振幅の分布は図４で表される。 Next, a correction method for conducting a theoretical analysis of one-dimensional heat conduction in the thickness direction and deriving a theoretical solution of the coating film surface temperature when a uniform sinusoidal bending moment acts will be described. When one side of the substrate is coated, the coordinate axis is set so that the intersection of the neutral surface in the substrate and the z-axis is the origin as shown in FIG. In that case, a uniaxial bending moment only in the x-axis direction of FIG. 3 is applied to the object to be measured, and the magnitude thereof varies in a sine wave shape. Therefore, the vertical stress amplitude in the y-axis direction in the base material has a linear distribution with respect to the z-axis direction. Further, assuming that the coating film is also deformed in accordance with the deformation of the base material, it is assumed that the strain is always equal at the interface between the base material and the coating film and uniform in the z-axis direction. Therefore, the distribution of stress amplitude and strain amplitude in the base material and the coating film is represented in FIG.
軸方向の１次元熱伝導のみを考慮すると、基礎式は次式で表される。 Considering only one-dimensional heat conduction in the axial direction, the basic equation is expressed by the following equation.
コーティング膜表面（ｚ＝（Lｍ／２）＋LＣ）における温度の理論解は、式（48）の第２式にｚ＝（Lｍ／２）＋LＣを代入することで得られ、それは次式で表される。 The theoretical solution of the temperature at the coating film surface (z = (L m / 2) + L C ) is obtained by substituting z = (Lm / 2) + LC into the second equation of equation (48), which is expressed by the following equation: It is represented by
前記従来の課題を解決するため、赤外線応力測定の補正方法および赤外線応力測定システムは、前記異なる振動周波数によって得られる熱弾性効果に基づく温度振幅成分の周波数特性を構成する測定データ数は、少なくとも前記変数の個数以上であり、減衰特性を表現可能な測定データ点数、すなわち温度振幅成分の周波数特性のみを用いた補正の場合には、少なくとも５個以上のデータが必要であり、温度振幅成分と位相成分の周波数特性両方を用いた場合には、温度振幅成分と位相成分のデータが各３個以上必要であることを特徴とする。 In order to solve the conventional problem, the infrared stress measurement correction method and the infrared stress measurement system have at least the measurement data number constituting the frequency characteristic of the temperature amplitude component based on the thermoelastic effect obtained by the different vibration frequencies. In the case of correction using only the number of measurement data points that can express the attenuation characteristics, that is, the number of variables, that is, only the frequency characteristics of the temperature amplitude component, at least five pieces of data are required. When both frequency characteristics of components are used, three or more data of temperature amplitude components and phase components are required.
前記従来の課題を解決するため、赤外線応力測定の補正方法および赤外線応力測定システムは、１次の熱伝導方程式をベースとして解を求めるため、適応範囲は主に厚さ方向および面内方向でおおよそ均一な応力場であることを特徴とする。 In order to solve the above-described conventional problems, the infrared stress measurement correction method and the infrared stress measurement system obtain a solution based on the first-order heat conduction equation, and thus the applicable range is approximately in the thickness direction and the in-plane direction. It is characterized by a uniform stress field.
前記従来の課題を解決するため、赤外線応力測定システムは、基材とコーティング膜両方の熱伝導および熱弾性効果を考慮した１次元の熱伝導方程式から求められるコーティング膜表面の温度振幅の理論解を、異なる振動周波数によって得られる熱弾性効果に基づく温度変化成分および位相成分の周波数特性に対して最小二乗法によりカーブフィッティングさせることによって前記コーティング膜表面の理論解の変数を同定し、コーティングによる熱伝導の影響を補正する機能を備えたことを特徴とする。 In order to solve the above-mentioned conventional problems, the infrared stress measurement system calculates a theoretical solution of the temperature amplitude of the coating film surface obtained from a one-dimensional heat conduction equation considering the heat conduction and thermoelastic effects of both the substrate and the coating film. The variable of the theoretical solution of the coating film surface is identified by curve fitting by the least square method to the frequency characteristics of the temperature change component and the phase component based on the thermoelastic effect obtained by different vibration frequencies, and the heat conduction by the coating It is characterized by having a function of correcting the influence of.
図５は、前記赤外線応力測定システムの測定および補正プロセスを示すフローチャートで、異なる振動周波数によって得られる熱弾性効果による温度振幅成分および位相成分の周波数特性を取得する応力測定の工程で取得した結果を用いて最小二乗法によるフィッティングから変数を同定し、補正した温度振幅もしくは主応力和を求める工程からなることを特徴とする。 FIG. 5 is a flowchart showing the measurement and correction process of the infrared stress measurement system, and shows the results obtained in the stress measurement step of obtaining the frequency characteristics of the temperature amplitude component and the phase component due to the thermoelastic effect obtained by different vibration frequencies. It is characterized by comprising a step of identifying a variable from the fitting by the least square method and obtaining a corrected temperature amplitude or principal stress sum.
具体的には、この測定プロセスは、異なる振動周波数によって得られる熱弾性効果による温度振幅成分および位相成分の周波数特性を取得する赤外線応力測定工程５ａと、減衰状態を判断する減衰状態判断工程５ｂと、補正工程５ｃを有している。赤外線応力測定工程５ａは、測定対象物に加える加振の加振周波数のセットと加振スタートを指示するステップＳ１と、測定対象物の温度画像を撮影している赤外線カメラから画像を取り込むステップＳ２と、ステップＳ２で取り込んだ画像信号を信号処理するステップＳ３と、ステップＳ３の結果に基づいて周波数特性をプロットするステップＳ４と、ステップＳ４におけるプロットの数ｎが規定数Ｎになったかを判定してステップＳ１〜Ｓ４のステップの繰り返しを制御するステップＳ５を有している。ステップＳ５においてプロット数が規定数Ｎになったことを検出すると、減衰状態判断工程５ｂがステップＳ６で減衰状態を判断する。補正工程５ｃは、減衰状態判断工程５ｂの結果に基づいてステップＳ７でフィッティングによる変数の同定を実行し、ステップＳ８では、温度変化量ｃ６を抽出する。さらに、ステップＳ９では、残渣ｒが既定値よりも小さくなったことを検出するまでステップＳ１〜Ｓ８を繰り返すように制御している。 Specifically, this measurement process includes an infrared stress measurement step 5a for acquiring frequency characteristics of a temperature amplitude component and a phase component due to thermoelastic effects obtained by different vibration frequencies, and an attenuation state determination step 5b for determining an attenuation state. And a correction step 5c. In the infrared stress measurement step 5a, a step S1 for instructing a vibration frequency to be applied to the object to be measured and a vibration start step S1, and a step S2 for capturing an image from an infrared camera that is taking a temperature image of the object to be measured. Step S3 for performing signal processing on the image signal captured in Step S2, Step S4 for plotting frequency characteristics based on the result of Step S3, and determining whether the number n of plots in Step S4 has reached the specified number N Step S5 for controlling the repetition of steps S1 to S4. When it is detected in step S5 that the number of plots has reached the specified number N, the attenuation state determination step 5b determines the attenuation state in step S6. Correction step 5c on the basis of the result of the decay state determining step 5b performs the identification of variables by fitting in step S7, in step S8, extracts the amount of temperature change c 6. Further, in step S9, control is performed so that steps S1 to S8 are repeated until it is detected that the residue r has become smaller than a predetermined value.
以下に、本発明の実施の形態について、図面を参照しながら説明する。
（実施の形態１）
図６は、本発明の実施の形態１における赤外線応力測定システムを示す。
Embodiments of the present invention will be described below with reference to the drawings.
(Embodiment 1)
FIG. 6 shows an infrared stress measurement system according to Embodiment 1 of the present invention.
測定対象物としての試験片１ｂは、基材とこの基材の表面に形成されたコーティング膜から構成されている。試験片１ｂを加振機１ａにセットする。コントロールデバイスＣＤでコントロールされた加振機１ａは、引張あるいは圧縮応力を試験片１ｂに繰返し加える。この試験片１ｂを、赤外線カメラ１ｃによって撮像する。赤外線カメラ１ｃによって取得した温度画像は、情報処理装置としてのパーソナルコンピュータＰＣで処理して応力値を計算する。ＦＧは加振波形を出力するファンクションジェネレータである。ファンクションジェネレータＦＧの出力信号は、分岐して赤外線カメラ１ｃとコントロールデバイスＣＤに供給されている。このようにファンクションジェネレータＦＧからの信号が入力されているコントロールデバイスＣＤによって加振機１ａの加振周波数を制御することで、赤外線カメラ１ｃの撮影画像と試験片１ｂに加えられる加振周波数を同期させている。 The test piece 1b as a measurement object is composed of a base material and a coating film formed on the surface of the base material. The test piece 1b is set on the vibrator 1a. The vibrator 1a controlled by the control device CD repeatedly applies tensile or compressive stress to the test piece 1b. The test piece 1b is imaged by the infrared camera 1c. The temperature image acquired by the infrared camera 1c is processed by a personal computer PC as an information processing apparatus to calculate a stress value. FG is a function generator that outputs an excitation waveform. The output signal of the function generator FG is branched and supplied to the infrared camera 1c and the control device CD. In this way, by controlling the excitation frequency of the shaker 1a by the control device CD to which the signal from the function generator FG is input, the captured image of the infrared camera 1c and the excitation frequency applied to the test piece 1b are synchronized. I am letting.
温度分布測定の赤外線カメラ１ｃには、赤外線カメラ(Cedip社，Silver480M)を用い、加振機１ａには、油圧サーボ疲労試験機(島津製作所，サーボパルサ，最大試験能力：10kN)を使用した。試験片１ｂには、基材としてＡＢＳのＪＩＳ規格に則ったダンベル型２号試験片を用いた。また、コーティング材として放射率が高い黒色つや消し塗料（アサヒペン，耐熱塗料）を用いて膜厚を３水準変化させて塗布を行った。この試験片に荷重振幅０．１ｋＮ，応力比Ｒ＝０として荷重を負荷した。なお加振周波数は１，３，５，１０，１５，２０，２５，３０Ｈｚと変数の数以上で温度振幅の減衰形状がわかる８種類とした。また、すべての実験において，赤外線カメラのフレームレートは２４９Ｈｚとした。また、コーティング膜厚を３種類（薄いほうからＮｏ．１〜Ｎｏ．３）変化させて測定した。実験より求めた温度振幅の周波数特性を図７（ａ）に、位相特性を図７（ｂ）に示す。図７（ａ）から温度振幅は加振周波数が高くなるにしたがって減衰している。更に、コーティング膜厚が増加するとその減衰はより顕著になる。また、図７（ｂ）の位相の周波数特性から、熱伝導の影響により、加振周波数によって位相はπから変化している。コーティング膜厚を３種類ｃ５ｉ（ｉ＝１，２，３），加振周波数を８種類ωｊ ＊（ｉ＝１，２，・・・８）と変化させて測定した結果に対して次式の目的関数にて最小二乗法を用いたカーブフィッティングを行った。 An infrared camera (Cedip, Silver480M) was used as the infrared camera 1c for temperature distribution measurement, and a hydraulic servo fatigue tester (Shimadzu Corporation, servo pulser, maximum test capability: 10 kN) was used as the vibration exciter 1a. As the test piece 1b, a dumbbell type No. 2 test piece conforming to the ABS JIS standard was used as a base material. In addition, application was performed by changing the film thickness by three levels using a black matte paint (Asahi pen, heat-resistant paint) having a high emissivity as a coating material. The test piece was loaded with a load amplitude of 0.1 kN and a stress ratio R = 0. The excitation frequencies are 1, 3, 5, 10, 15, 20, 25, and 30 Hz, which are eight types in which the attenuation shape of the temperature amplitude can be understood by the number of variables or more. In all experiments, the frame rate of the infrared camera was 249 Hz. Moreover, it measured by changing three types of coating film thickness (No.1-No.3 from the thinner one). FIG. 7A shows the frequency characteristic of the temperature amplitude obtained from the experiment, and FIG. 7B shows the phase characteristic. From FIG. 7A, the temperature amplitude attenuates as the excitation frequency increases. Furthermore, the attenuation becomes more pronounced as the coating thickness increases. Further, from the frequency characteristics of the phase in FIG. 7B, the phase changes from π depending on the excitation frequency due to the influence of heat conduction. The following results are obtained by measuring the coating film thickness with three types c 5i (i = 1, 2, 3) and the excitation frequency with eight types ω j * (i = 1, 2,... 8). Curve fitting using the least squares method was performed with the objective function of the equation.
（実施の形態２）
本発明の基材とコーティング膜から構成され、単軸引張り応力が付加される測定対象物の赤外線応力測定で得られる応力値の補正方法において、コーティング膜厚が１水準であっても補正が可能であることを説明する。実製品では、コーティング膜厚を種々変化させて熱弾性応力測定を行うことは困難である場合が多い。そこで、次式のように目的関数をおいて、コーティング膜厚毎に実験値に対して最小二乗法によるカーブフィッティングを行い、コーティング膜厚が１種類であった場合のカーブフィッティングを行った。カーブフィッティングを行う実験データである温度振幅および位相の周波数特性は実施の形態１で用いた図７（ａ）と図７（ｂ）のデータを使用した。
(Embodiment 2)
In the method for correcting the stress value obtained by measuring the infrared stress of a measurement object composed of a substrate and a coating film according to the present invention and to which a uniaxial tensile stress is applied, correction is possible even if the coating film thickness is one level. Explain that. In actual products, it is often difficult to perform thermoelastic stress measurement by varying the coating film thickness. Accordingly, an objective function is set as in the following equation, and curve fitting by the least square method is performed on the experimental value for each coating film thickness, and curve fitting is performed when the coating film thickness is one type. The data of FIG. 7A and FIG. 7B used in the first embodiment are used for the frequency characteristics of temperature amplitude and phase, which are experimental data for performing curve fitting.
（実施の形態３）
本発明の基材とコーティング膜から構成され、単軸引張り応力が付加される測定対象物の赤外線応力測定で得られる応力値の補正方法において、基材としてＳＵＳ３０４を用いた場合にＡＢＳと同様な補正が可能かを検討した。温度分布測定は、実施の形態１の図６に示した装置を使用した。また、コーティング材として放射率が高い黒色つや消し塗料(アサヒペン，耐熱塗料)を用いて膜厚を３水準変化させて塗布を行った。これらの試験片を試験機に設置し、荷重振幅３．０ｋＮ，応力比Ｒ＝０として荷重を負荷した。なお加振周波数は１，３，５，１０，１５，２０，２５，３０Ｈｚと変数の数以上で温度振幅の減衰形状がわかる８種類とした。また、すべての実験において、赤外線カメラのフレームレートは２４９Ｈｚとし、コーティング膜厚を３種類（薄いほうからＮｏ．１〜Ｎｏ．３）変化させて測定した。実験より求めた温度振幅の周波数特性を図１０（ａ）に、温度位相特性を図１０（ｂ）に示す。図１０（ａ）から温度振幅は加振周波数が高くなるにしたがって減衰している。更に、コーティング膜厚が増加するとその減衰はより顕著になる。また、図１０（ｂ）の温度位相の周波数特性から、熱伝導の影響により、加振周波数によって位相はπから変化している。コーティング膜厚を３種類ｃ５ｉ（ｉ＝１，２，３），加振周波数を８種類ωｊ ＊（ｉ＝１，２，・・・８）と変化させて測定した結果に対して次式の目的関数にて最小二乗法を用いたカーブフィッティングを行った。
(Embodiment 3)
In the method for correcting a stress value obtained by infrared stress measurement of an object to be measured, which is composed of a base material and a coating film of the present invention and to which a uniaxial tensile stress is applied, it is the same as ABS when SUS304 is used as the base material. We examined whether correction was possible. The apparatus shown in FIG. 6 of Embodiment 1 was used for temperature distribution measurement. In addition, coating was performed by changing the film thickness by three levels using a black matte paint (Asahi pen, heat-resistant paint) having a high emissivity as a coating material. These test pieces were installed in a testing machine and loaded with a load amplitude of 3.0 kN and a stress ratio R = 0. The excitation frequencies are 1, 3, 5, 10, 15, 20, 25, and 30 Hz, which are eight types in which the attenuation shape of the temperature amplitude can be understood by the number of variables or more. In all experiments, the frame rate of the infrared camera was 249 Hz, and the coating film thickness was measured by changing three types (from the thinner to No. 1 to No. 3). FIG. 10A shows the frequency characteristics of the temperature amplitude obtained from the experiment, and FIG. 10B shows the temperature phase characteristics. From FIG. 10A, the temperature amplitude attenuates as the excitation frequency increases. Furthermore, the attenuation becomes more pronounced as the coating thickness increases. Further, from the frequency characteristics of the temperature phase in FIG. 10B, the phase changes from π depending on the excitation frequency due to the influence of heat conduction. The following results are obtained by measuring the coating film thickness with three types c 5i (i = 1, 2, 3) and the excitation frequency with eight types ω j * (i = 1, 2,... 8). Curve fitting using the least squares method was performed with the objective function of the equation.
（実施の形態４）
本発明の基材とコーティング膜から構成され、単軸引張り応力が付加される測定対象物の赤外線応力測定で得られる応力値の補正方法において、コーティング膜厚が１水準であっても補正が可能であることを説明する。実製品では、コーティング膜厚を種々変化させて熱弾性応力測定を行うことは困難である場合が多い。そこで、次式のように目的関数をおいて、コーティング厚さ膜厚毎に実験値に対して最小二乗法によるカーブフィッティングを行い、コーティング膜厚が１種類であった場合のカーブフィッティングを行った。カーブフィッティングを行う実験データである温度振幅の周波数特性と温度位相特性は実施の形態３で用いた図１０（ａ）と図１０（ｂ）を使用した。
(Embodiment 4)
In the method for correcting the stress value obtained by measuring the infrared stress of a measurement object composed of a substrate and a coating film according to the present invention and to which a uniaxial tensile stress is applied, correction is possible even if the coating film thickness is one level. Explain that. In actual products, it is often difficult to perform thermoelastic stress measurement by varying the coating film thickness. Therefore, using the objective function as in the following equation, curve fitting by the least square method was performed on the experimental value for each coating thickness, and curve fitting was performed when the coating thickness was one type. . FIG. 10A and FIG. 10B used in the third embodiment are used for the frequency characteristics and temperature phase characteristics of temperature amplitude, which are experimental data for performing curve fitting.
（実施の形態５）
図１３は、本発明の実施の形態３における基材とコーティング膜から構成され、曲げモーメントが付加される測定対象物の赤外線応力測定で得られる応力値の補正方法に必要な熱弾性効果測定で求められる温度振幅の周波数特性を取得する実験システムを示す。
(Embodiment 5)
FIG. 13 shows a thermoelastic effect measurement necessary for a method of correcting a stress value obtained by measuring an infrared stress of a measurement object composed of a base material and a coating film according to Embodiment 3 of the present invention and to which a bending moment is added. The experimental system which acquires the frequency characteristic of the required temperature amplitude is shown.
温度分布測定は、赤外線カメラ(Cedip社，Silver480M)１ｃを用い、加振機１ａには、エミック社製５１３−Ａの電磁式加振機を用いた。測定対象物１ｂｂは、基材として幅１５ｍｍ、厚み１５ｍｍ、長さ３００〜４００ｍｍのＡＢＳを用い、曲げモーメントを一様に付加するために中央１０２ｍｍ間をボルトで固定し、治具を介して加振機１ａに接続した。また、測定対象物１ｂｂの裏側にはひずみゲージ１ｆを添付し、赤外線カメラ１ｃで取得した温度振幅を応力へ変換した値を同じ周波数で測定したひずみゲージ１ｆから取得したひずみから算出した応力で規格化することによって周波数特性を求めた。 For the temperature distribution measurement, an infrared camera (Cedip, Silver480M) 1c was used, and a 513-A electromagnetic vibrator made by Emic was used as the vibrator 1a. The object to be measured 1bb uses an ABS having a width of 15 mm, a thickness of 15 mm, and a length of 300 to 400 mm as a base material. In order to uniformly apply a bending moment, the center 102 mm is fixed with a bolt and added via a jig. Connected to the vibrator 1a. Further, a strain gauge 1f is attached to the back side of the measurement object 1bb, and the value obtained by converting the temperature amplitude obtained by the infrared camera 1c into stress is converted from the stress obtained from the strain gauge 1f measured at the same frequency, and is standardized. Thus, the frequency characteristics were obtained.
コーティング材として放射率が高い黒色つや消し塗料(アサヒペン，耐熱塗料)を用いて膜厚を３水準変化させて塗布を行った。これらの試験片を試験機に設置し、加振周波数を１〜１００Ｈｚとし、周波数を変化させて赤外線カメラおよびひずみゲージを用いて測定を行った。なお、その時に取得するデータ数は、未知の変数の数以上で温度振幅および位相の周波数特性の形状がわかる数７以上とした。また、すべての実験において、赤外線カメラ１ｃのフレームレートは２４９Ｈｚであった。ＦＧは加振波形を出力するファンクションジェネレータ、ＰＡは加振波形で加振機１ａをドライブする第１増幅器、ＳＡはひずみゲージ１ｆの出力信号を処理する第２増幅器、ＰＣは情報処理装置としてのパーソナルコンピュータで、赤外線カメラ１ｃの映像信号をひずみゲージ１ｆの出力信号に基づいて処理する。もしくは、パーソナルコンピュータＰＣは、赤外線カメラ１ｃの映像信号をひずみゲージ１ｆの出力信号とファンクションジェネレータＦＧからの制御信号に基づいて処理する。 Coating was performed by changing the film thickness by three levels using a black matte paint (Asahi pen, heat-resistant paint) having a high emissivity as a coating material. These test pieces were installed in a testing machine, the excitation frequency was set to 1 to 100 Hz, and the frequency was changed to perform measurement using an infrared camera and a strain gauge. It should be noted that the number of data acquired at that time was set to be 7 or more, which indicates the shape of the frequency characteristics of the temperature amplitude and phase with the number of unknown variables or more. In all experiments, the frame rate of the infrared camera 1c was 249 Hz. FG is a function generator that outputs an excitation waveform, PA is a first amplifier that drives the exciter 1a with the excitation waveform, SA is a second amplifier that processes the output signal of the strain gauge 1f, and PC is an information processing device A personal computer processes the video signal of the infrared camera 1c based on the output signal of the strain gauge 1f. Alternatively, the personal computer PC processes the video signal of the infrared camera 1c based on the output signal of the strain gauge 1f and the control signal from the function generator FG.
また、コーティング膜厚を３種類（薄いほうからＮｏ．１〜Ｎｏ．３）変化させて測定した。実験より求めた温度振幅の周波数特性を図１４（ａ）に、位相特性を図１４（ｂ）に示す。図１４（ａ）から温度振幅は加振周波数が高くなるにしたがって減衰している。更に、コーティング膜厚が増加するとその減衰はより顕著になる。また、図１４（ｂ）の位相の周波数特性から、熱伝導の影響により、加振周波数によって位相はπから変化している。コーティング膜厚を３種類Eｉ（ｉ＝１，２，３），加振周波数を１６種類ωｊ ＊（ｉ＝１，２，・・・１６）と変化させて測定した結果に対して次式の目的関数にて最小二乗法を用いたカーブフィッティングを行った。 Moreover, it measured by changing three types of coating film thickness (No.1-No.3 from the thinner one). FIG. 14A shows the frequency characteristics of the temperature amplitude obtained from the experiment, and FIG. 14B shows the phase characteristics. From FIG. 14A, the temperature amplitude attenuates as the excitation frequency increases. Furthermore, the attenuation becomes more pronounced as the coating thickness increases. Further, from the frequency characteristics of the phase in FIG. 14B, the phase changes from π depending on the excitation frequency due to the influence of heat conduction. The following results are obtained by measuring the coating film thickness with three types E i (i = 1, 2, 3) and the excitation frequency with 16 types ω j * (i = 1, 2,... 16). Curve fitting using the least squares method was performed with the objective function of the equation.
（実施の形態６）
本発明の実施の形態３における基材とコーティング膜から構成され、曲げモーメントが付加される測定対象物の赤外線応力測定で得られる応力値の補正方法において、実施の形態５で検討したＡＢＳと同様にステンレス材ＳＵＳ３０４においても補正可能であることを検討した。温度振幅の分布測定は、実施の形態５で示したように、赤外線カメラ(Cedip社，Silver480M)を用い、加振機には、エミック社製５１３−Ａの電磁式加振機を用いた。測定対象物は、基材として幅１０ｍｍ、厚み３ｍｍ、長さ３００〜４００ｍｍのステンレス材ＳＵＳ３０４を用い、曲げモーメントを一様に付加するために中央１０２ｍｍ間をボルトで固定し、治具を介して加振機に接続した。また、試験片の裏側にはひずみゲージを添付し、赤外線カメラで取得した温度振幅を応力へ変換した値を同じ周波数で測定したひずみゲージから取得したひずみから算出した応力で規格化することによって周波数特性を求めた。
(Embodiment 6)
In the method for correcting the stress value obtained by the infrared stress measurement of the measurement object composed of the base material and the coating film according to the third embodiment of the present invention and to which a bending moment is added, it is the same as the ABS studied in the fifth embodiment. In addition, it was examined that correction is possible even in the stainless steel SUS304. As shown in the fifth embodiment, an infrared camera (Cedip, Silver480M) was used for temperature amplitude distribution measurement, and an electromagnetic vibrator 513-A made by Emic was used as the vibrator. The object to be measured uses a stainless steel material SUS304 having a width of 10 mm, a thickness of 3 mm, and a length of 300 to 400 mm as a base material. Connected to a shaker. In addition, a strain gauge is attached to the back side of the test piece, and the frequency is normalized by the stress calculated from the strain acquired from the strain gauge measured at the same frequency. The characteristics were determined.
コーティング材として放射率が高い黒色つや消し塗料(アサヒペン，耐熱塗料)を用いて膜厚を３水準変化させて塗布を行った。これらの試験片を試験機に設置し、加振周波数を１〜１００Ｈｚとし、周波数を変化させて赤外線カメラおよびひずみゲージを用いて測定を行った。なお、その時取得するデータ数は、未知の変数の数以上で温度振幅および位相の周波数特性の形状がわかる数７以上とした。また、すべての実験において、赤外線カメラのフレームレートは２４９Ｈｚであった。 Coating was performed by changing the film thickness by three levels using a black matte paint (Asahi pen, heat-resistant paint) having a high emissivity as a coating material. These test pieces were installed in a testing machine, the excitation frequency was set to 1 to 100 Hz, and the frequency was changed to perform measurement using an infrared camera and a strain gauge. It should be noted that the number of data acquired at that time was set to 7 or more, which indicates the shape of the frequency characteristics of the temperature amplitude and phase with the number of unknown variables or more. In all experiments, the frame rate of the infrared camera was 249 Hz.
また、コーティング膜厚を３種類（薄いほうからＮｏ．１〜Ｎｏ．３）変化させて測定した。実験より求めた温度振幅の周波数特性を図１６（ａ）に、位相特性を図１６（ｂ）に示す。図１６（ａ）から温度振幅は加振周波数が高くなるにしたがって減衰している。更に、コーティング膜厚が増加するとその減衰はより顕著になる。また、図１６（ｂ）の位相の周波数特性から、熱伝導の影響により、加振周波数によって位相はπから変化している。コーティング膜厚さを３種類Eｉ（ｉ＝１，２，３），加振周波数を１６種類ωｊ ＊（ｉ＝１，２，・・・１６）と変化させて測定した結果に対して次式の目的関数にて最小二乗法を用いたカーブフィッティングを行った。 Moreover, it measured by changing three types of coating film thickness (No.1-No.3 from the thinner one). FIG. 16A shows the frequency characteristic of the temperature amplitude obtained from the experiment, and FIG. 16B shows the phase characteristic. From FIG. 16A, the temperature amplitude attenuates as the excitation frequency increases. Furthermore, the attenuation becomes more pronounced as the coating thickness increases. In addition, from the frequency characteristics of the phase in FIG. 16B, the phase changes from π depending on the excitation frequency due to the influence of heat conduction. With respect to the measurement results when the coating film thickness is changed to 3 types E i (i = 1, 2, 3) and the excitation frequency is changed to 16 types ω j * (i = 1, 2,... 16). Curve fitting using the least squares method was performed with the objective function of the following equation.
（実施の形態７）
本発明の実施の形態３における基材とコーティング膜から構成され、曲げモーメントが付加される測定対象物の赤外線応力測定で得られる応力値の補正方法において、実施の形態５および実施の形態６で検討したＡＢＳ、ＳＵＳ３０４と同様にアルミ材Ａ６０６３においても補正可能であることを検討した。温度振幅の分布測定は、実施の形態５で示したように、赤外線カメラ(Cedip社，Silver480M)を用い、加振機には、エミック社製５１３−Ａの電磁式加振機を用いた。測定対象物は、基材として幅１０ｍｍ、厚み５ｍｍ、長さ３００〜４００ｍｍのアルミ材Ａ６０６３を用い、曲げモーメントを一様に付加するために中央１０２ｍｍ間をボルトで固定し、治具を介して加振機に接続した。また、試験片の裏側にはひずみゲージを添付し、赤外線カメラで取得した温度振幅を応力へ変換した値を同じ周波数で測定したひずみゲージから取得したひずみから算出した応力で規格化することによって周波数特性を求めた。
(Embodiment 7)
In a method for correcting a stress value obtained by infrared stress measurement of an object to be measured, which is composed of a base material and a coating film according to Embodiment 3 of the present invention and to which a bending moment is added, in Embodiment 5 and Embodiment 6. Similar to the studied ABS and SUS304, the aluminum material A6063 was considered to be correctable. As shown in the fifth embodiment, an infrared camera (Cedip, Silver480M) was used for temperature amplitude distribution measurement, and an electromagnetic vibrator 513-A made by Emic was used as the vibrator. The object to be measured uses an aluminum material A6063 having a width of 10 mm, a thickness of 5 mm, and a length of 300 to 400 mm as a base material, and a center 102 mm is fixed with bolts to uniformly apply a bending moment, and a jig is interposed. Connected to a shaker. In addition, a strain gauge is attached to the back side of the test piece, and the frequency is normalized by the stress calculated from the strain acquired from the strain gauge measured at the same frequency. The characteristics were determined.
コーティング材として放射率が高い黒色つや消し塗料(アサヒペン，耐熱塗料)を用いて膜厚を３水準変化させて塗布を行った。これらの試験片を試験機に設置し、加振周波数を１〜１００Ｈｚとし、周波数を変化させて赤外線カメラおよびひずみゲージを用いて測定を行った。なお、その時取得するデータ数は、未知の変数の数以上で温度振幅および位相の周波数特性の形状がわかる数７以上とした。また、すべての実験において、赤外線カメラのフレームレートは２４９Ｈｚであった。 Coating was performed by changing the film thickness by three levels using a black matte paint (Asahi pen, heat-resistant paint) having a high emissivity as a coating material. These test pieces were installed in a testing machine, the excitation frequency was set to 1 to 100 Hz, and the frequency was changed to perform measurement using an infrared camera and a strain gauge. It should be noted that the number of data acquired at that time was set to 7 or more, which indicates the shape of the frequency characteristics of the temperature amplitude and phase with the number of unknown variables or more. In all experiments, the frame rate of the infrared camera was 249 Hz.
また、コーティング膜厚さを３種類（薄いほうからＮｏ．１〜Ｎｏ．３）変化させて測定した。実験より求めた温度振幅の周波数特性を図１８（ａ）に、位相特性を図１８（ｂ）に示す。図１８（ａ）から温度振幅は加振周波数が高くなるにしたがって減衰している。更に、コーティング膜厚が増加するとその減衰はより顕著になる。また、図１８（ｂ）の位相の周波数特性から、熱伝導の影響により、加振周波数によって位相はπから変化している。コーティング膜厚さEｉ（ｉ＝１，２，３），加振周波数を１６種類ωｊ ＊（ｉ＝１，２，・・・１６）と変化させて測定した結果に対して次式の目的関数にて最小二乗法を用いたカーブフィッティングを行った。 Moreover, it measured by changing three types of coating film thickness (No.1-No.3 from the thinner one). FIG. 18A shows the frequency characteristic of the temperature amplitude obtained from the experiment, and FIG. 18B shows the phase characteristic. From FIG. 18A, the temperature amplitude attenuates as the excitation frequency increases. Furthermore, the attenuation becomes more pronounced as the coating thickness increases. In addition, from the frequency characteristics of the phase in FIG. 18B, the phase changes from π depending on the excitation frequency due to the influence of heat conduction. The coating thickness E i (i = 1, 2, 3) and the excitation frequency are changed to 16 types ω j * (i = 1, 2,... 16). Curve fitting using the least squares method was performed with the objective function.
（実施の形態８）
本発明の基材とコーティング膜から構成され、一軸応力が付加される測定対象物のコーティングによる熱伝導の影響を補正する機能を備えた赤外線応力測定システムについて、補正プロセスが有効に機能するかを検討した。温度分布測定は、実施の形態１の図６に示した装置を使用した。試験対象には、基材としてＡＢＳのＪＩＳ規格に則ったダンベル型２号試験片を用いた。また、コーティング材として放射率が高い黒色つや消し塗料(アサヒペン，耐熱塗料)を用いて膜厚を３水準変化させて塗布を行った。これらの試験片を試験機に設置し、荷重振幅０．１ｋＮ，応力比Ｒ＝０として荷重を負荷した。なお加振周波数は変数が７個よりも多い８個とし、減衰特性を表現できるように１，３，５，１０，１５，２０，２５，３０Ｈｚと変えて、すべての実験において、赤外線カメラのフレームレートは２４９Ｈｚとした。また、コーティング膜厚さは１種類で測定した。実験より求めた温度振幅の周波数特性を図２０（ａ）に、温度位相特性を図２０（ｂ）に示す。図２０（ａ）から温度振幅は加振周波数が高くなるにしたがって減衰している状態が判断できたので、次の補正工程で補正を行う。次の補正工程では、コーティング膜厚さを１種類C5，加振周波数を８種類ωｊ ＊（ｉ＝１，２，・・・８）と変化させて測定した結果に対して式（66）の目的関数にて最小二乗法を用いたカーブフィッティングを行った。
(Embodiment 8)
Whether or not the correction process functions effectively for an infrared stress measurement system comprising the substrate of the present invention and a coating film and having a function of correcting the influence of heat conduction due to the coating of a measurement object to which uniaxial stress is applied. investigated. The apparatus shown in FIG. 6 of Embodiment 1 was used for temperature distribution measurement. As a test object, a dumbbell type No. 2 test piece in accordance with ABS JIS standard was used as a base material. In addition, coating was performed by changing the film thickness by three levels using a black matte paint (Asahi pen, heat-resistant paint) having a high emissivity as a coating material. These test pieces were installed in a testing machine, and a load was applied with a load amplitude of 0.1 kN and a stress ratio R = 0. The excitation frequency is 8 more than 7 variables, and is changed to 1, 3, 5, 10, 15, 20, 25, and 30 Hz so that attenuation characteristics can be expressed. The frame rate was 249 Hz. Moreover, the coating film thickness was measured by one type. FIG. 20A shows the frequency characteristic of the temperature amplitude obtained from the experiment, and FIG. 20B shows the temperature phase characteristic. Since it has been determined from FIG. 20A that the temperature amplitude is attenuated as the excitation frequency increases, correction is performed in the next correction step. In the next correction step, the equation (66) is applied to the measurement results obtained by changing the coating film thickness to one type C 5 and the excitation frequency to eight types ω j * (i = 1, 2,... 8). Curve fitting using the least square method was performed with the objective function of).
（実施の形態９）
本発明の実施の形態８における基材とコーティング膜から構成され、曲げモーメントが付加される測定対象物の赤外線応力測定で得られる応力値の補正方法に必要な熱弾性効果測定で求められる温度振幅および位相の周波数特性を取得する実験システムについて補正プロセスが有効に機能するかを検討した。温度分布測定は、赤外線カメラ(Cedip社，Silver480M)を用い、加振機には、エミック社製５１３−Ａの電磁式加振機を用いた。測定対象物は、基材として幅１５ｍｍ、厚み１５ｍｍ、長さ３００〜４００ｍｍのＡＢＳを用い、曲げモーメントを一様に付加するために中央１０２ｍｍ間をボルトで固定し、治具を介して加振機に接続した。また、試験片の裏側にはひずみゲージを添付し、赤外線カメラで取得した温度振幅を応力へ変換した値を同じ周波数で測定したひずみゲージから取得したひずみから算出した応力で規格化することによって周波数特性を求めた。
(Embodiment 9)
Temperature amplitude obtained by thermoelastic effect measurement required for a method of correcting a stress value obtained by infrared stress measurement of a measurement object composed of a base material and a coating film in Embodiment 8 of the present invention and to which a bending moment is added And we investigated whether the correction process works effectively for the experimental system to obtain the frequency characteristics of the phase. For the temperature distribution measurement, an infrared camera (Cedip, Silver480M) was used, and a 513-A electromagnetic shaker manufactured by Emic was used as the shaker. The object to be measured uses an ABS having a width of 15 mm, a thickness of 15 mm, and a length of 300 to 400 mm as a base material. In order to uniformly apply a bending moment, the center 102 mm is fixed with a bolt, and is vibrated through a jig. Connected to the machine. In addition, a strain gauge is attached to the back side of the test piece, and the frequency is normalized by the stress calculated from the strain acquired from the strain gauge measured at the same frequency. The characteristics were determined.
コーティング材として放射率が高い黒色つや消し塗料(アサヒペン，耐熱塗料)を用いて膜厚を１水準変化させて塗布を行った。これらの試験片を試験機に設置し、加振周波数を１〜１００Ｈｚとし、周波数を変化させて赤外線カメラおよびひずみゲージを用いて測定を行った。なお、その時取得するデータ数は、未知の変数の数以上で温度振幅および位相の周波数特性の形状がわかる数７以上とした。また、すべての実験において、赤外線カメラのフレームレートは２４９Ｈｚであった。 The coating was performed by changing the film thickness by one level using a black matte paint (Asahi pen, heat-resistant paint) having a high emissivity as a coating material. These test pieces were installed in a testing machine, the excitation frequency was set to 1 to 100 Hz, and the frequency was changed to perform measurement using an infrared camera and a strain gauge. It should be noted that the number of data acquired at that time was set to 7 or more, which indicates the shape of the frequency characteristics of the temperature amplitude and phase with the number of unknown variables or more. In all experiments, the frame rate of the infrared camera was 249 Hz.
実験より求めた温度振幅の周波数特性を図２２（ａ）に、位相特性を図２２（ｂ）に示す。図２２（ａ）から温度振幅は加振周波数が高くなるにしたがって減衰している。更に、コーティング膜厚が増加するとその減衰はより顕著になる。また、図２２（ｂ）の位相の周波数特性から、熱伝導の影響により、加振周波数によって位相はπから変化している。加振周波数を１６種類ωｊ ＊（ｉ＝１，２，・・・１６）と変化させて測定した結果に対して式（67）の目的関数にて最小二乗法を用いたカーブフィッティングを行った。 The frequency characteristic of the temperature amplitude obtained from the experiment is shown in FIG. 22A, and the phase characteristic is shown in FIG. From FIG. 22A, the temperature amplitude attenuates as the excitation frequency increases. Furthermore, the attenuation becomes more pronounced as the coating thickness increases. Further, from the frequency characteristics of the phase in FIG. 22B, the phase changes from π depending on the excitation frequency due to the influence of heat conduction. Curve fitting using the least squares method with the objective function of Equation (67) is performed on the measurement results obtained by changing the excitation frequency to 16 types ω j * (i = 1, 2,... 16). It was.
（実施の形態１０）
本発明の実施の形態１０における赤外線応力測定の補正方法を備えたシステムを実際の道路、鉄道などの高架を構成する橋梁に適応した場合について説明する。
(Embodiment 10)
A case where the system including the infrared stress measurement correction method according to the tenth embodiment of the present invention is applied to a bridge constituting an actual road, railway, or the like will be described.
図２４に示す橋梁においては、橋梁下面に位置する主桁２４は、鉄骨（Ｈ鋼）を基材とし、この表面をコーティング膜としての塗膜で塗装して構成され、橋梁上面を通過する車両の荷重を支えるため、曲げモーメントによる応力が発生する。車両通過時に発生する熱弾性効果による温度変化成分および位相の測定は、赤外線カメラ(Cedip社，Silver480M)を用い、重量２０トンの車両を用いて、車両通過時に発生する荷重変動を加振機の代わりに用いた。異なる振動周波数によって得られる熱弾性効果に基づく温度変化成分および位相成分の周波数特性を測定するため、重量２０トンの車両の通過速度を時速１０ｋｍ／ｈ〜６０ｋｍ／ｈまで、５ｋｍ／ｈステップで変化させ１２回の測定を行った。また、位相成分の周波数特性は、フレーム間に生じる測定対象物である橋梁の位置変化量から求めた。また、すべての実験において、赤外線カメラのフレームレートは２４９Ｈｚであった。 In the bridge shown in FIG. 24, the main girder 24 located on the lower surface of the bridge is configured by using a steel frame (H steel) as a base material and painting the surface with a coating film as a coating film, and passing through the upper surface of the bridge. Stress due to bending moment is generated to support the load. The temperature change component and phase due to the thermoelastic effect that occurs when the vehicle passes are measured using an infrared camera (Cedip, Silver480M) and a 20-ton vehicle, and the fluctuation in load that occurs when the vehicle passes is Used instead. In order to measure the frequency characteristics of the temperature change component and phase component based on the thermoelastic effect obtained by different vibration frequencies, the passing speed of a vehicle with a weight of 20 tons is changed in steps of 5 km / h from 10 km / h to 60 km / h. The measurement was performed 12 times. The frequency characteristic of the phase component was obtained from the amount of change in the position of the bridge, which is a measurement object generated between frames. In all experiments, the frame rate of the infrared camera was 249 Hz.
実験より求めた温度振幅の周波数特性を図２５（ａ）に、位相特性を図２５（ｂ）に示す。図２５（ａ）から温度振幅は加振周波数が高くなるにしたがって減衰している。更に、コーティング膜厚が増加するとその減衰はより顕著になる。また、図２５（ｂ）の位相の周波数特性から、熱伝導の影響により、加振周波数によって位相はπから変化している。車両通過時に発生する温度変化成分および位相成分の周波数を１２種類ωｊ ＊（ｉ＝１，２，・・・１２）と変化させて測定した結果に対して式（68）の目的関数にて最小二乗法を用いたカーブフィッティングを行った。 FIG. 25A shows the frequency characteristic of the temperature amplitude obtained from the experiment, and FIG. 25B shows the phase characteristic. From FIG. 25A, the temperature amplitude attenuates as the excitation frequency increases. Furthermore, the attenuation becomes more pronounced as the coating thickness increases. Further, from the frequency characteristics of the phase in FIG. 25B, the phase changes from π depending on the excitation frequency due to the influence of heat conduction. The objective function of equation (68) is used for the measurement result obtained by changing the frequency of the temperature change component and the phase component generated when passing the vehicle to 12 types ω j * (i = 1, 2,... 12). Curve fitting using the least square method was performed.
なお、今回の検討では重量２０トンの車両を用いて、車両通過時に発生する荷重変動を加振機の代わりに用いたが、周波数を変えて荷重変動することによって熱弾性効果による温度変化を生じさせることが可能な方法であれば、どのような方法でも同様な結果が得られる。 In this study, a vehicle with a weight of 20 tons was used, and the load fluctuation that occurred when passing through the vehicle was used instead of the vibration exciter. However, the temperature change caused by the thermoelastic effect was caused by changing the load at different frequencies. Similar methods can be obtained by any method that can be used.
本発明は、基材とコーティング膜から構成される測定対象物において、コーティングによる熱伝導の影響を補正することにより正しい応力値、応力分布を求めることが可能であり、製品や部品のコーティング膜を剥がすことなく正確な応力の値や分布を得ることができ、応力集中部などの危険部位を正確に判断し、不安全事象を未然に防止する上で有用である。 In the present invention, it is possible to obtain a correct stress value and stress distribution by correcting the influence of heat conduction by coating on a measurement object composed of a base material and a coating film. Accurate stress values and distribution can be obtained without peeling off, and it is useful for accurately determining dangerous parts such as stress concentration parts and preventing unsafe events.
１ａ 加振機
１ｂ 試験片
１ｂｂ 測定対象物
１ｃ 赤外線カメラ
１ｆ ひずみゲージ
ＣＤ コントロールデバイス
ＰＣ パーソナルコンピュータ
ＦＧ ファンクションジェネレータ
ｘ ｙｚの２軸と直行する方向
ｙ 荷重の負荷方向
ｚ コーティング膜厚方向
５ａ 赤外線応力測定工程
５ｂ 減衰状態判断工程
５ｃ 補正工程
DESCRIPTION OF SYMBOLS 1a Exciter 1b Test piece 1bb Measurement object 1c Infrared camera 1f Strain gauge CD Control device PC Personal computer FG Function generator xyz Direction orthogonal to two axes y Load direction z Coating film thickness direction 5a Infrared stress measurement process 5b Attenuation state determination process 5c Correction process
Claims (10)
基材とコーティング膜両方の熱伝導および熱弾性効果に基づく１次元の熱伝導方程式から求められるコーティング膜表面の温度振幅の理論解を、異なる振動周波数によって得られる熱弾性効果に基づく温度変化成分および位相成分の周波数特性に対して最小二乗法によりカーブフィッティングさせることによって前記コーティング膜表面の理論解の変数を同定し、コーティングによる熱伝導の影響を補正する、
赤外線応力測定システムにおける応力値の補正方法。 A measurement object composed of a base material and a coating film is vibrated, and the measurement object is photographed with an infrared camera to measure the temperature amplitude of the measurement object. From this measurement result, the stress value of the measurement object is measured. In the infrared stress measurement system
A theoretical solution of the temperature amplitude of the coating film surface obtained from a one-dimensional heat conduction equation based on the heat conduction and thermoelastic effects of both the base material and the coating film, and a temperature change component based on the thermoelastic effect obtained by different vibration frequencies and Identify the variables of the theoretical solution on the surface of the coating film by curve fitting to the frequency characteristics of the phase component by the least square method, and correct the influence of heat conduction by the coating;
A method for correcting a stress value in an infrared stress measurement system.
請求項１記載の赤外線応力測定システムにおける応力値の補正方法。 Temperature change component based on thermoelastic effect obtained by different vibration frequency from theoretical solution of temperature amplitude of coating film surface obtained from one-dimensional heat conduction equation based on heat conduction and thermoelastic effect of both base material and coating film, and The frequency characteristic of the phase component is a measurement object on which uniaxial stress acts,
A method for correcting a stress value in the infrared stress measurement system according to claim 1.
請求項１記載の赤外線応力測定システムにおける応力値の補正方法。 Temperature change component based on thermoelastic effect obtained by different solution frequency and theoretical solution of temperature amplitude of coating film surface obtained from one-dimensional heat conduction equation considering thermal conductivity and thermoelastic effect of both substrate and coating film And the frequency characteristic of the phase component is a measurement object on which a bending moment acts,
A method for correcting a stress value in the infrared stress measurement system according to claim 1.
請求項１〜３のいずれかに記載の赤外線応力測定システムにおける応力値の補正方法。 An infrared stress measurement method using a thermoelastic effect, wherein the variables constituting the theoretical solution of the temperature amplitude of the one-dimensional heat conduction equation are the ratio of the physical property values of the substrate and the coating film and the coating of the substrate It is represented by the ratio of the thickness of the film,
The correction method of the stress value in the infrared stress measurement system in any one of Claims 1-3.
請求項４に記載の赤外線応力測定システムにおける応力値の補正方法。 An infrared stress measurement method using a thermoelastic effect, wherein the number of variables constituting the theoretical solution of the temperature amplitude of the one-dimensional heat conduction equation is 5 or more,
A method for correcting a stress value in the infrared stress measurement system according to claim 4.
請求項４または請求項５に記載の赤外線応力測定システムにおける応力値の補正方法。 An infrared stress measurement method using a thermoelastic effect, wherein the physical property values are Young's modulus, Poisson's ratio, density, constant pressure specific heat, thermal expansion coefficient, thermal conductivity,
A method for correcting a stress value in the infrared stress measurement system according to claim 4 or 5.
請求項１〜６のいずれかに記載の赤外線応力測定システムにおける応力値の補正方法。 Infrared stress measurement method using the thermoelastic effect, and the data constituting the frequency characteristics of the temperature change component and the phase component based on the thermoelastic effect obtained by the different vibration frequencies are at least the number of the variables and the attenuation curve. It is the number of measurement points that can represent the shape,
A method for correcting a stress value in the infrared stress measurement system according to claim 1.
請求項１〜７のいずれかに記載の赤外線応力測定システムにおける応力値の補正方法。 An infrared stress measurement method using a thermoelastic effect, wherein the infrared stress measurement using the thermoelastic effect is mainly a stress field in a thickness direction and an in-plane direction,
The correction method of the stress value in the infrared stress measurement system in any one of Claims 1-7.
測定対象物を撮影する赤外線カメラと、
前記赤外線カメラの温度振幅画像を処理して前記測定対象物の応力値を求める情報処理装置とを有し、
前記情報処理装置は、
基材とコーティング膜両方の熱伝導および熱弾性効果に基づく１次元の熱伝導方程式から求められるコーティング膜表面の温度振幅の理論解を、異なる振動周波数によって得られる熱弾性効果に基づく温度変化成分および位相成分の周波数特性に対して最小二乗法によりカーブフィッティングさせることによって前記コーティング膜の表面の理論解の変数を同定し、前記コーティング膜による熱伝導の影響を補正して前記測定対象物に作用する応力値を計算する、
赤外線応力測定システム。 An infrared stress measurement system for vibrating a measurement object, photographing the measurement object with an infrared camera, and calculating a stress value acting on the measurement object using a thermoelastic effect,
An infrared camera for photographing the measurement object;
An information processing device that calculates a stress value of the measurement object by processing a temperature amplitude image of the infrared camera;
The information processing apparatus includes:
A theoretical solution of the temperature amplitude of the coating film surface obtained from a one-dimensional heat conduction equation based on the heat conduction and thermoelastic effects of both the base material and the coating film, and a temperature change component based on the thermoelastic effect obtained by different vibration frequencies and The variable of the theoretical solution on the surface of the coating film is identified by curve fitting to the frequency characteristic of the phase component by the least square method, and the influence of heat conduction by the coating film is corrected to act on the measurement object. Calculate stress values,
Infrared stress measurement system.
請求項９記載の赤外線応力測定システム。 The infrared stress measurement system according to claim 9, further comprising a vibrator that repeatedly applies tensile or compressive stress to the measurement object.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2018146857A1 (en) | 2017-02-10 | 2018-08-16 | パナソニックＩｐマネジメント株式会社 | Stress measurement method, stress measurement device, and stress measurement system |
| CN112824867A (en) * | 2019-11-21 | 2021-05-21 | 湖南大学 | Method and device for testing fatigue limit of metal material |
| CN117172163A (en) * | 2023-08-15 | 2023-12-05 | 重庆西南集成电路设计有限责任公司 | Amplitude and phase two-dimensional optimization method and system of amplitude and phase control circuit, medium and electronic equipment |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH10274570A (en) * | 1997-03-28 | 1998-10-13 | Jeol Ltd | Infrared stress display device |
| US5918283A (en) * | 1996-08-20 | 1999-06-29 | The University Of Sheffield | Coating for thermoelasticity |
| JP2006029963A (en) * | 2004-07-15 | 2006-02-02 | Takahide Sakagami | Method and device for measuring degree of thermal influence by plastic deformation |
| JP2010223957A (en) * | 2009-02-25 | 2010-10-07 | Panasonic Corp | Fatigue limit identification system, fatigue breakdown area identifying method, and fatigue limit identifying method |
-
2014
- 2014-07-22 JP JP2014148403A patent/JP6223294B2/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5918283A (en) * | 1996-08-20 | 1999-06-29 | The University Of Sheffield | Coating for thermoelasticity |
| JPH10274570A (en) * | 1997-03-28 | 1998-10-13 | Jeol Ltd | Infrared stress display device |
| JP2006029963A (en) * | 2004-07-15 | 2006-02-02 | Takahide Sakagami | Method and device for measuring degree of thermal influence by plastic deformation |
| JP2010223957A (en) * | 2009-02-25 | 2010-10-07 | Panasonic Corp | Fatigue limit identification system, fatigue breakdown area identifying method, and fatigue limit identifying method |
Non-Patent Citations (1)
| Title |
|---|
| 柳沢伸 他: "熱弾性応力測定の精度に及ぼす表面コーティングの影響", 日本機械学会Ｍ＆Ｍ材料力学カンファレンスＣＤ−ＲＯＭ論文集, vol. 2013, JPN6017024091, 10 October 2013 (2013-10-10), pages 0609, ISSN: 0003596530 * |
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2018146857A1 (en) | 2017-02-10 | 2018-08-16 | パナソニックＩｐマネジメント株式会社 | Stress measurement method, stress measurement device, and stress measurement system |
| JP2018128431A (en) * | 2017-02-10 | 2018-08-16 | パナソニックＩｐマネジメント株式会社 | Stress measurement system and stress measurement method |
| US20190353538A1 (en) * | 2017-02-10 | 2019-11-21 | Panasonic Intellectual Property Management Co., Ltd. | Stress measurement method, stress measurement device, and stress measurement system |
| EP3561468A4 (en) * | 2017-02-10 | 2020-01-22 | Panasonic Intellectual Property Management Co., Ltd. | Stress measurement method, stress measurement device, and stress measurement system |
| US11467046B2 (en) | 2017-02-10 | 2022-10-11 | Panasonic Intellectual Property Management Co., Ltd. | Stress measurement method, stress measurement device, and stress measurement system |
| CN112824867A (en) * | 2019-11-21 | 2021-05-21 | 湖南大学 | Method and device for testing fatigue limit of metal material |
| CN112824867B (en) * | 2019-11-21 | 2022-11-25 | 湖南大学 | Method and device for testing fatigue limit of metal material |
| CN117172163A (en) * | 2023-08-15 | 2023-12-05 | 重庆西南集成电路设计有限责任公司 | Amplitude and phase two-dimensional optimization method and system of amplitude and phase control circuit, medium and electronic equipment |
| CN117172163B (en) * | 2023-08-15 | 2024-04-12 | 重庆西南集成电路设计有限责任公司 | Amplitude and phase two-dimensional optimization method and system of amplitude and phase control circuit, medium and electronic equipment |
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